2007-01-15 15:21:34 · 13 answers · asked by L 1 in Cars & Transportation ➔ Other - Cars & Transportation
Bridges freeze before the road because bridges are off the ground. The ground stays warmer because of the mantal under the crust. Just because the crust is thick doesn't mean that the ground in some places can't still be warm. Where I live there are 5 inactive volcanos on the outside of the city. When it snows the snow never sticks because of how warm the ground is.
2007-01-15 15:33:00 · answer #1 · answered by LilyDragon 3 · 0⤊ 1⤋
Because there's air flowing under the bridge where a road is insulated by the ground underneath to keep it from freezing first.
2007-01-15 15:25:34 · answer #2 · answered by Tiki™ 4 · 2⤊ 0⤋
Because bridges have cold air passing above AND below them, whereas roads on the ground are insulated by the earth so they don't reach freezing temperatures as quickly.
2007-01-15 15:29:38 · answer #3 · answered by Anonymous · 1⤊ 0⤋
Because the brige cools faster then road. Since the bridge is suspended in the air the cold air can cool both sides. Unlike the roads one top side. Roads stay warmer longer do to the earth.
2007-01-15 15:26:47 · answer #4 · answered by kakl1104 2 · 1⤊ 0⤋
the roads contain oils that slow down the prosses of freezing. it depends on the bridge but it is usually because the cold air can traval all the way around the bridge causing it to freeze faster.
2007-01-15 15:30:18 · answer #5 · answered by FFCarlos 2 · 0⤊ 2⤋
moisture in the air coupled with the cold wind coming from the water coupled with fact that the wind can blow on top and bottom of the bridge where as the rest of the road is laid on top of the earth which keeps it warmer longer
2007-01-15 15:27:05 · answer #6 · answered by getbyone 3 · 0⤊ 0⤋
The air circulation under the bridge lowers the temp.
2007-01-15 15:25:27 · answer #7 · answered by John L 5 · 3⤊ 0⤋
They are suspended over the land or water. It takes a lot to freeze land so it tends to keep anything in direct contact with it a little warmer than something in the air.
2007-01-15 15:29:21 · answer #8 · answered by ♫ giD∑■η ♫ 5 · 2⤊ 0⤋
cold air travels below a bridge -cooling it from all sides
2007-01-15 15:26:16 · answer #9 · answered by frozenbrew 4 · 0⤊ 0⤋
because air can get under them,,this make the temperature go down a lot faster on the surface of the bridge,,good luck i hope this help,s.
2007-01-15 15:25:33 · answer #10 · answered by dodge man 7 · 2⤊ 1⤋